A semiconductor device (i.e., chip) is designed to function properly below a set temperature threshold. When the device operates below this threshold temperature, it performs within desired parameters. But if its temperature rises above this threshold, the performance of the device may degrade and it may begin to experience logic errors. Furthermore, if the temperature of the chip rises high enough, it may suffer permanent damage, rendering the chip useless for its designed function.
One source of heat is environmental, i.e., the temperature of the area in which the device is operated; another source of heat is from the device itself. During normal operation, the semiconductor device will generate a certain amount of waste heat. This amount of internally-generated waste heat only increases as the clock frequency and circuit density on a chip increase, and its die size decreases.
In order to minimize the chance of chips overheating, many products incorporating semiconductor chips include elements to minimize the temperature of the chips. These can include heat sinks, fans, or the like. In addition, products incorporating semiconductor chips are often placed in temperature-controlled rooms to better maintain an acceptable temperature.
Despite precautions, however, it may be difficult to guarantee that any given chip will be maintained below its threshold temperature. Therefore, many chips will include a temperature sensor that indicates when the temperature of the chip rises to a dangerous level. By monitoring the output of such a temperature sensor, a product incorporating the semiconductor chip can determine when the temperature of the chip is rising too high and take necessary precautions (e.g., slowing down the clock speed of the chip, shutting the chip down for a time, etc.).
But a rising trend in electronic products can serve to complicate this temperature monitoring operation. Many electronic products include multiple chips within a single package. These multiple-chip products or multiple-chip packages (MCPs) each contain more than one semiconductor chip, and each chip may have its own temperature sensor. This may result in an MCP controller that receives multiple temperature-sensing signals, and will require that the MCP controller be provided with a mechanism for processing these multiple temperature-sensing signals in an effective and efficient manner.